- A great deal of the Rust in this repo is thanks to ramenspazz's Pico_I2S project for this same hardware set (Pimoroni Pico Audio shield on the Pi Pico) - in Rust.
- This project uses the pio I2S assembly provided by raspberrypi/pico-extras.
You'll need to install Rust Embedded toolchains, see the Rust Embedded book for details there.
cargo run --release
Will flash a Pi Pico that is in USB boot mode.
Butterworth first order filter
- center_frequency = 146 # Center frequency in Hz
- sample_rate = 44100 # Sample rate in Hz
- bandwidth = 0.2 # Bandwidth as a percentage
Butterworth Filter Coefficients for DSP Implementation:
- Numerator (b): [ 0.00414308 0. -0.00414308]
- Denominator (a): [ 1. -1.99130017 0.99171384]
y[n]=b[0]×x[n]+b[1]×x[n−1]+⋯+a[1]×y[n−1]+…
- where x[n] is your input signal, and y[n] is your filtered output signal.
I've authored a test binary to generate WAV file outputs for debug iteration in the host environment.
cargo test --test main --target x86_64-unknown-linux-gnu